// Public documentation sample: no WingsFlow imports, sessions or DB access.
export async function integrate(
  base,
  key,
  {
    channelId,
    templateId,
    externalId = 'customer-842',
    fetchImpl = fetch,
  } = {},
) {
  const send = async (method, path, body, idem) => {
    const response = await fetchImpl(base + path, {
      method,
      headers: {
        Authorization: `Bearer ${key}`,
        ...(body
          ? { 'Content-Type': 'application/json', 'Idempotency-Key': idem }
          : {}),
      },
      ...(body ? { body: JSON.stringify(body) } : {}),
    });
    const json = await response.json();
    if (!response.ok)
      throw new Error(
        `${response.status} ${json.error?.code} ${json.error?.request_id}`,
      );
    return json.data;
  };
  const me = await send('GET', '/me'),
    channels = await send('GET', '/channels');
  channelId ??= channels[0]?.id;
  if (!channelId) throw new Error('No granted channel; ask administrator');
  const templates = await send('GET', '/templates?channel_id=' + channelId);
  templateId ??= templates[0]?.id;
  const selected = templates.find((t) => t.id === templateId);
  if (!selected) throw new Error('No granted approved template');
  const contact = await send(
    'PUT',
    '/contact-identities/' + encodeURIComponent(externalId),
    { phone: '+919876543210', name: 'Documentation fixture' },
    externalId + '-profile-v1',
  );
  const event = await send(
    'POST',
    '/events',
    {
      source_event_id: externalId + ':order:ORD-123:created:v1',
      event: 'order.created',
      schema_version: '1',
      occurred_at: '2026-09-14T06:30:00Z',
      contact_id: contact.id,
      data: {
        order_id: 'ORD-123',
        aggregate_version: 1,
        amount_minor: 2500000,
        currency: 'INR',
      },
      correlation_id: 'order:ORD-123',
    },
    externalId + '-order-created-v1',
  );
  return { tenantId: me.tenant_id, contact, event, channelId, templateId };
}